The present invention relates to an arrangement for a rotor bearing, particularly for a rapidly rotating spinning turbine in an open-end spinning machine, of the type including an axial bearing.
It has previously been proposed to provide a bearing arrangement in which the rotor to be mounted has a journal entending into a bearing bush, as disclosed in German patent application No. P 24 27 055.1 and the corresponding, commonly assigned U.S. application Ser. No. 695,551, filed June 14th 1976. It has now been found that sufficient lubricant supply is not always assured for the axial bearing of such an arrangement. The reason for this would appear to be the centrifugal forces encountered as a result of the high rate of rotation, exceeding 40,000 rpm, usually employed in present-day spinning turbines for open-end spinning processes, resulting in ejection of the lubricant out of the axial bearing.
German Offenlegungsschrift [Laid Open Application] No. 2,256,052 discloses a spinning unit in which aerodynamic or aerostatic bearings are provided to support the shaft in the radial or axial direction, respectively. Here, too, the danger exists with respect to the axial bearing that the lubricating medium will be conveyed radially outwardly to a substantial degree so that either large quantities of gas must pass through the bearing or the cost of the bearing manufacturing process is greatly increased due, for example, to the provision of spiral grooves. Moreover, due to the use of pressure plates for the axial bearing, production and assembly of the spinning unit is rather complicated and removal of the spinning unit can be achieved only with difficulty.